FEATURE: Add reversed and type to allowed attributes (PR #14626)

RE: Support reversed lists in posts by not stripping the "reversed" attribute from HTML - feature - Discourse Meta

Added reversed and type for ordered lists to the allowed attributes.


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I am approving this, generally we add tests to confirm we do not have regressions, but I do not want to block the merge here, I feel there are plenty other attributes missing regression tests, might as well add a test for all of the missing ones later in 1 go.